Topical medications have been used to treat or prevent many conditions. For some medications, it is important to carefully control the amount of medication being applied to the skin to minimize unwanted side effects. Disposable sheets, wipes or pads have been used to apply topical medications. These topical applicators are made of absorbent material which carries the medication and wiping the skin treatment area with them allows for some transfer of medication. However, a significant amount of the medication can remain trapped in the absorbent material and thus be wasted. Also, the amount of medication that is transferred to the skin is highly dependent upon the technique of the user. For example, lightly pressing the pad on the skin will result in less drug transfer than using greater pressure and the amount of drug can also be dependent on the number of times the skin is wiped (with dose increasing with the number of passes). Moreover, the use of such absorbent material (or even other topical medications that are formulated as creams or lotions) also results in drug being transferred to the hands (whether it is the patient or caregiver) which could lead to excess exposure or inadvertent transfer to the administrator's eyes, mouth or other people.
Conventional applicator devices, such as roll-on balls, rub-on sticks and aerosol spray cans, can also present difficulty in controlling the amount of medication being applied to the skin. With such devices, the amount of medication dispensed can vary greatly day to day. For ball and stick applicators, the amount of medication dispensed can depend on the time duration at which the applicator is rolled or rubbed against the skin. For common aerosol spray cans, the amount of medication dispensed can depend on the time duration at which the nozzle valve is depressed by the user.
What is needed are a device and method that allows the user to control the amount and location of drug or active ingredient being dispensed so that a consistent and predictable amount is dispensed. Such control can prevent sub-effective dose from under-dosing as well as minimize waste of the drug and/or minimize unwanted side effects that may arise with excessive drug administration. What is also needed are a device and method for dispensing a drug that encourages the user to apply a prescribed or recommended dose of the drug.